Technical Interview Questions

What is an Aggregate Function(s)
Aggregate Function will take more than one data element and combine into whole result
What is a Trigger
Trigger is a database object associated with a table. When you perform a defined action on a table such as INSERT, UPDATE, DELETE it will execute a set of actions on a table.
The difference between truncate and delete
IaaS vs PaaS vs SaaS
  • IaaS - Infrastructure as a Service provides all the equipment for a customer such as networking, data storage, and hardware with use of internet. It up to the customer to implement their own Operating System (OS), software, deployments, testing, performance metrics, etc. You are basically renting the hardware and networking infrastructure. All maintence on the infrastructure is owned by the provider.
    Examples: Amazon Web Services (AWS), RackSpace, Microsoft Azure
  • PaaS - Platform as a Service includes IaaS but customer provides only the application and data. The customer does not have to worry about OS updates, software upgrades, data storage etc. The customer can focus on the creation of the apps.
    Examples: Windows Azure, AWS Elastic Beanstalk, Google App Engine
  • SaaS - Software as a Service is all of the above plus the applications are created and updated by the provider. The customer is the user.
    Examples: Cisco WebEx, Google Apps, Salesforce